Initial commit

.gitignore

@@ -0,0 +1 @@
+config.lua

config.example.lua

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+-- vim: set sw=4 ts=4 sts=4 et :
+
+config = {
+    wifi = {
+        ssid = "homeassistant",
+        pwd = "somereallylongandsecurewpapassphrasehopefully"
+    },
+    mqtt = {
+        host = "192.168.1.10",
+        clientid = "client1",
+        user = "homeassistant",
+        pwd = "mqttpassword",
+        keepalive = 120,
+        topic = "buttons/basement"
+    },
+    buttons = {
+        [1] = "theatre_lights",
+        [2] = "main_basement_lights",
+        [7] = "office_lights"
+    }
+}

init.lua

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+-- vim: set sw=4 ts=4 sts=4 et :
+
+function main()
+    dofile("config.lua")
+    dofile("mqttbutton.lua")
+
+    mqttbutton_main()
+end
+
+-- Wait 1 second before starting. If there is a bug that crashes the
+-- microcontroller, this hopefully gives enough time to delete the program.
+tmr.alarm(0, 1000, 0, main)

mqttbutton.lua

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+-- vim: set sw=4 ts=4 sts=4 et :
+
+WIFI_TIMER_ID = 1
+
+function gpiosetup()
+    local k, v
+    if (config.buttons ~= nil) then
+        for pin, payload in pairs(config.buttons) do
+            gpio.mode(pin, gpio.INT)
+            gpio.trig(pin, "down", function(level)
+                if (gpio.read(pin) == gpio.LOW) then
+                    on_button_press(pin, payload)
+                end
+            end)
+        end
+    end
+end
+
+function mqttsetup()
+    if (mqtt_client == nil) then
+        mqtt_client = mqtt.Client(
+            config.mqtt.clientid,
+            config.mqtt.keepalive,
+            config.mqtt.user,
+            config.mqtt.pwd
+        )
+        mqtt_client:on("connect", on_mqtt_connected)
+        mqtt_client:on("offline", on_mqtt_disconnected)
+    end
+    mqtt_client:connect(config.mqtt.host)
+end
+
+function on_button_press(pin, payload)
+    print("Button pressed: " .. pin)
+    if (mqtt_client ~= nil) then
+        mqtt_client:publish(config.mqtt.topic, payload, 0, 0)
+    end
+end
+
+function on_mqtt_connected(client)
+    print("MQTT Connected")
+end
+
+function on_mqtt_disconnected(client)
+    print("MQTT Disconnected")
+    client:close()
+    on_wifi_timer()
+end
+
+function on_wifi_connected()
+    mqttsetup()
+end
+
+function on_wifi_timer()
+    local status = wifi.sta.status()
+    if (status == 0) then -- Idle
+        wifi.sta.connect()
+        tmr.alarm(WIFI_TIMER_ID, 250, 0, on_wifi_timer)
+    elseif (status == 1) then  -- Connecting
+        tmr.alarm(WIFI_TIMER_ID, 250, 0, on_wifi_timer)
+    elseif (status == 5) then -- Connected
+        local ip = wifi.sta.getip()
+        if (ip ~= nil) then
+            print("WiFi Connected: " .. wifi.sta.getip())
+            on_wifi_connected()
+        else
+            tmr.alarm(WIFI_TIMER_ID, 250, 0, on_wifi_timer)
+        end
+    else -- Error
+        print("WiFi Connection Error: " .. status)
+        tmr.alarm(WIFI_TIMER_ID, 1000, 0, on_wifi_timer)
+    end
+end
+
+function mqttbutton_main()
+    wifisetup()
+    gpiosetup()
+end
+
+function wifisetup()
+    if (wifi.getmode() ~= wifi.STATION) then
+        wifi.setmode(wifi.STATION)
+    end
+
+    wifi.sta.config(config.wifi.ssid, config.wifi.pwd)
+    tmr.alarm(WIFI_TIMER_ID, 250, 0, on_wifi_timer)
+end